ObjectDB Database Search

and sometimes we don't get the entity by query. Have you an idea what happens here?   btc_es BTC EmbeddedSystems

named queries instead of dynamic queries may improve code organization by separating the JPQL ... carefully to avoid collision (e.g. by using the unique entity name as a prefix). It makes sense to add ... at Runtime Named queries are represented at runtime by the same Query and TypedQuery interfaces

Queries are represented in JPA 2 by two interfaces - the old Query interface ... with an EntityManager (represented by em in the following code snippets), which serves as a factory ... which retrieves all the Country objects in the database is represented by both q1 and q2 . When building

Existing entity objects can be deleted from the database either explicitly by invoking the remove ... committed the object is not deleted. An IllegalArgumentException is thrown by remove if the argument ... should be cascaded automatically to entity objects that are referenced by that field (multiple entity objects

: This page explains how ObjectDB configuration works in general. The Configuration Path By default ... explicitly by setting the "objectdb.home" system property: System.setProperty("objectdb.home", "/odb ... : java "-Dobjectdb.home=/odb" ... The Configuration File As noted above, by default the configuration

by fields that are marked with CascadeType . PERSIST or CascadeType . ALL are also persisted ... yet are also persisted. Automatic Change Tracking As shown above, an update is achieved by modifying a managed ... demonstrated above, array changes are not detected automatically ( by default) but it is possible

This chapter demonstrates basic ObjectDB and JPA concepts by introducing a simple example program ... that contains points in the plane. Each point is represented by an object with two int fields, x and y, that hold the point's x and y coordinates. The program demonstrates CRUD database operations by

"false" ) specifies if SSL is used. As shown above, SSL is disabled by default. It could be enabled ... signature. This file is generated from the Keystore file by omitting the private key ... . If authenticating the client machine by the server is also required a Keystore file (which might be different

grouped by the application, and which must be colocated in their mapping to a single database ... to create and remove persistent entity instances, to find entities by their primary key, and to query over entities. The set of entities that can be managed by a given EntityManager instance

As demonstrated in this forum thread , a mapped by collection field with lazy fetch mode is not initialized in results of a query that uses JOIN FETCH on that collection field (when enhancement is used). support Support   Build 2.4.1_06 fixes this issue (fields are now initialized

, other schema changes are handled by ObjectDB automatically. Note: Extreme caution is required ... is changed from the original name, which is specified by the required name attribute, to the new name ... attribute is specified the class name is changed from the original name, which is specified by

of the Java Data Objects (JDO) API than competing object databases. By using a standard API such as JPA ... relational database by using an ORM JPA provider such as Hibernate, EclipseLink or Open JPA ... . The support of two standard APIs (JPA and JDO) by ObjectDB minimizes the risk

) is that in JPA data is represented by classes and objects rather than by tables and records as in ... of the Java Persistence API (JPA). By interacting with ObjectDB using standard JPA

In JPA a database connection is represented by the EntityManager interface. Therefore, in order ... by ObjectDB to be a database URL rather than a persistence unit name. The $objectdb variable represents the ObjectDB home directory ( by default - the directory in which ObjectDB is installed

of an entity class are detected by ObjectDB. New entity objects have to be stored in the new class ... again. Conversion of an entity object to the new schema is done on a field by field basis: For every field ... ) The automatic schema evolution mechanism, as described above, is based on matching fields by

This chapter introduced the basic principles of JPA using ObjectDB. You can go into details by ... your own ObjectDB/JPA projects simply by modifying this sample program. Reading the Next Chapters ... the picture by describing some tools and settings that are specific to ObjectDB:

collection after query execution (e.g. by results.get(0) ). To eliminate this routine operation JPA ... = (Long)query. getSingleResult (); An aggregate COUNT query always returns one result, by definition ... - the executeUpdate method returns the number of objects that have been updated or deleted by the query

. The four relationship modes are represented by the following annotations: Unlike ORM JPA ... annotations are supported by ObjectDB for the inverse side of a bidirectional relationship (which is calculated by a query) : Details about all these annotations are provided in Chapter 2 of the ObjectDB manual.

In this final step we will add a simple table to the report: Open the [Insert Table] dialog box by ... ) layout. Set the column number to 2 , number of details to 1 , select the data set (e.g. Points by X ) in the third field and click OK . Fill the table with data by dragging the x and y columns from

We start by creating a new Eclipse Dynamic Web Project: Open the [New Project] dialog box, e.g. by ... as a new server by clicking the New Runtime... button . Follow the instructions and specify the path ... web project. Now, add ObjectDB support to the new Eclipse Project - by dragging the objectdb

The Guest entity objects will be stored in an ObjectDB database, which will be represented by ... created if not existing yet) when the web application starts, by instantiating ... down), by closing the  EntityManagerFactory . To register a ServletContextListener : Open the [New

] dialog box by right clicking the WEB-INF node under the Web Pages node (in the [Projects] window ... , which contains a simple form for signing the guestbook, followed by a list of all the guests that have already signed (which are retrieved from the request's guestDao attribute that is set by

the [New Java Class] dialog box, e.g. by right clicking the project node (in the [Package Explorer] window ... + ")"; } } The Guest entity class will represents guests in the database. We also need to configure JPA by setting a META-INF/persistence.xml file: Open the [New Folder] dialog box, e.g. by right clicking the project

a basic guestbook page. Every visitor can sign the guestbook by filling a simple form. The visitors that have already signed are listed below the form: Persistence is managed by JPA. Every visitor that has signed the guestbook is represented by a  Guest JPA entity object and all the  Guest

You can run the application now by right clicking the Main node (in the [Projects] window ... 1,000 objects. You can view the content of the database file by opening it in the ObjectDB Explorer : This is the end of the tutorial. Learn more about ObjectDB and JPA by reading the Manual .

The  JPA Web Application tutorial provides step by step instructions on how to build a simple ... . Building a new application step by step is an effective way to learn - but if you prefer ... ) If  Maven is installed - extract the zip and run the application from the command line by

application manages a basic guestbook page. Every visitor can sign the guestbook by filling a simple form. The visitors that have already signed are listed below the form: Persistence is managed by JPA. Every visitor that has signed the guestbook is represented by a Guest entity object

We start by creating a new Java EE dynamic web project in Eclipse: Open the [New Project] dialog box, e.g. by using File New Project... Select Web Dynamic Web Project and click Next . Choose ... runtime. Note: You may have to add GlassFish 3 as a new server by clicking the New Runtime... button

the [New Entity Class] dialog box, e.g. by right clicking the project node (in the [Projects] window ... to the project (under Configuration Files). Open the persistence.xml file in a text editor ( by right clicking and selecting Edit or by double click and then moving to the Source or XML tab in

can sign the guestbook by filling a simple form. The visitors that have already signed are listed below the form: Persistence is managed by JPA. Every visitor that has signed the guestbook is represented by a  Guest entity object and all the  Guest entity objects are stored in an ObjectDB

] dialog box by right clicking the Web Pages node (in the [Projects] window) and selecting New JSP ... a simple form for signing the guestbook, followed by a list of all the guests that have already signed (which are retrieved from the request's "guests" attribute that is set by the servlet in

You can now run the application by right clicking the Main.java file (in the [ Package Explorer ] window) and selecting Run As Java Application . The expected output in the Eclipse [Console] window ... by opening it in the ObjectDB Explorer : This is the end of the Eclipse JPA tutorial. Learn more about ObjectDB and JPA by reading the Manual .

manages a basic guestbook page. Every visitor can sign the guestbook by filling a simple form. The visitors that have already signed are listed below the form: Persistence is managed by JPA. Every visitor that has signed the guestbook is represented by a Guest JPA entity object and all the Guest

can sign the guestbook by filling a simple form. The visitors that have already signed are listed below the form: Persistence is managed by JPA. Every visitor that has signed the guestbook is represented by a Guest entity object and all the Guest entity objects are stored in an ObjectDB database

. The demo web application manages a basic guestbook page. Every visitor can sign the guestbook by ... is managed by JPA. Every visitor that has signed the guestbook is represented by a Guest entity object

The Getting Started with JPA tutorial provides step by step instructions on how to build a simple JPA database driven application in Eclipse or NetBeans . Building a new application step by step ... ) If Maven is installed - extract the zip and run the application from the command line by : mvn test

can sign the guestbook by filling a simple form. The visitors that have already signed are listed below the form: Persistence is managed by JPA. Every visitor that has signed the guestbook is represented by a  Guest entity object and all the  Guest entity objects are stored in an ObjectDB

To store objects in an ObjectDB database using JPA we need to define an entity class: Open the [New Entity Class] dialog box, e.g. by right clicking the project node (in the [Projects] window ... a text editor ( by right clicking and selecting Edit or by double click and then moving to the XML

. Every visitor can sign the guestbook by filling a simple form. The visitors that have already signed are listed below the form: Persistence is managed by JPA. Every visitor that has signed the guestbook is represented by a Guest entity object and all the Guest entity objects are stored in

] dialog box by right clicking the Web Pages node (in the [Projects] window) and selecting New JSP ... a simple form for signing the guestbook, followed by a list of all the guests that have already signed (which are retrieved from the request's "guests" attribute that is set by the servlet in

] dialog box by right clicking the WebContent node (in the [Package Explorer] window), selecting ... the guestbook, followed by a list of all the guests that have already signed (which are retrieved from the request's "guests" attribute that is set by the servlet in the previous step). The next step

] dialog box by right clicking WEB-INF under src/main/webapp (in the [Package Explorer] window ... the guestbook, followed by a list of all the guests that have already signed (which are retrieved from the request's  guestDao attribute that is set by the controller in the previous step

box by right clicking the guest package node (in the [Projects] window) and selecting New Servlet ... to generate the page output. Notice that operations on the database are carried on by the  GuestDao session bean, which is instantiated and injected by the application server into the 

] dialog box by right clicking the WebContent node (in the [Package Explorer] window), selecting ... generates the guestbook page output, which contains a simple form for signing the guestbook, followed by ... " attribute that is set by the servlet in the previous step). The next step (and the last one in this tutorial) is running the web application .

In this step we will add a servlet to manage guestbook web requests: Open the [Create Servlet] dialog box by right clicking the guest package node (in the [Package Explorer] window), selecting  ... on the database are carried on by the GuestDao session bean, which is instantiated and injected by

. This category includes members defined in the default fetch group in xml or annotations. Redefining the default fetch group via the API does not affect the members defined by this category. Using this category also sets the fetch-depth for the members in the default fetch group . Since: JDO 2.2

should be retrieved. The fields in the current fetch group must be retrieved, and the implementation might retrieve more fields than the current fetch group . If the useFetchPlan parameter is false ... , all fields in the current fetch plan are fetched, and other fields might be fetched lazily by

values should be retrieved. The fields in the current fetch group must be retrieved, and the implementation might retrieve more fields than the current fetch group . If the useFetchPlan parameter is false ... , all fields in the current fetch plan are fetched, and other fields might be fetched lazily by

should be retrieved. The fields in the current fetch group must be retrieved, and the implementation might retrieve more fields than the current fetch group . If the useFetchPlan parameter is false ... , all fields in the current fetch plan are fetched, and other fields might be fetched lazily by

technology by Sun Microsystems. The main purpose of this guide is to familiarise you with ObjectDB ... class is and which types are supported by JDO. Chapter 4 - JDO Metadata Shows how to define JDO ... you may want to extend your knowledge of JDO by reading the JDO specification or a book on JDO